Data loss when using Thunar and SFTP connection

[trinidad]

Hmmm? Scratching my head myself. Public IP convention. AES, matched users,  should work fine. I don't have any 2.8 around here anymore so I can't enable your set up exactly. Plus my Linux to Linux ssh connections are always interface bound ad hoc, or interface bound wired, and almost always to a Debian server. I know open ssh server is not code expressed exactly the same as far as root login between trusty and xenial, and RHEL and Debian, but you're not getting a no route to host error, and using a public IP convention with matching user names, so I'm guessing we've narrowed it down to a difference between older Mint and newer Ubuntu somewhere, i/e trusty leafpad, and xenial ssh, or an XFCE modification difference between 2.8 and 3.0 which will not let the kernels interface at some levels of function while default Debian gnome gedit seems to work fine. The other issue is I rarely use leafpad myself, either nano, redit, gedit, or kate, and sometimes when applicable Libreoffice. By the way there are some basic code options in Libreoffice, >LO greeting page >tools>Libreoffice drop down menu>Basic IDE Options. In Solydx I had to write fire wall rules to connect ssh but yours is already working so that's not it either, or you might have to enable x forwarding on the server side, and add (-x) to a long ssh URI address to /LO application/ then file, for Libreoffice to work seamlessly, and probably a vnc viewer on the client side to produce its remote desktop. Again I mostly use RDP and Samba protocols at the same time, so I have not experienced your particular situation. 

Out of ideas for now. Still thinking though. Ease of networking is a very important feature for any OS, and a source of constant tinkering and mistakes for many users of all experience levels. I'm always looking for the best, simplest, and safest solutions. Good Luck.

TC